Phthalocyanine lakes



PHTHALOCYANINE LAKES Robert E. Brouillard, Westfield, and Thomas D. Mutafiis, North Plainiield, N. 1., assignors to General Aniline & Film Corporation, New York, N. Y., a corporation of Delaware No Drawing. Application September 18, 1953, Serial No. 381,149

13 Claims. (Cl. 106-289) This invention relates to phthalocyanine lakes and more particularly to an improved process for the manufacture of metallic resinate lakes of phthalocyanine colors.

The phthalocyanine pigments are a group of brilliant blue to green tinctorially stable compounds of great importance in the pigmentation of surface coating compositions. Although this group of pigments excels all other in general fastness properties, they sulfer from texture and rheological deficiencies.

The texture of a pigment has been defined as the ability of the pigment to disperse to complete strength and freedom from grit aggregates. In the usual processing technique for the manufacture of phthalocyanine pigments the crude bases as obtained from the reaction mixtures are acid pasted and then dried. During the drying operation hard aggregates are formed which are not entirely ruptured by hammer milling and are dispersed to fine ultimate particle size only with considerable difficulty. This difficulty in dispersion causes great concern in the manufacture of paints, enamels, lacquers, printin g inks, linoleum, and colored plastics because an excessively long grinding in the vehicle becomes necessary to achieve maximum color value and adequate gloss in the final composition.

Phthalocyanines are rheologically deficient since, when formulated into lithographic varnishes, the printing ink systems produced are very short and buttery and are therefore lacking in tack and ability to feed properly from the printing press fountains.

Many attempts have been made to improve the texture and rheological properties Otf the phthalocyanine pigments. One of such attempts is disclosed in United States Letters Patent No. 2,173,699 which describes resinations. Although the process described in this patent represents a substantial improvement over the prior art, it is lacking in that large product quality variations result from small differences in processing technique and the pigmentary texture obtained is deficient. Thus, agitation, resin quality variations, pH of the system, and many uncontrollable factors profoundly effect the quality of the pigment produced. Furthermore, the phthalocyanine to be resinated must be specially prepared to be suitable. Still further, the product obtained develops relatively slowly in strength and freedom from grit when ground into a vehicle.

It is an object of this invention to provide a process for the preparation of phthalocyanine lakes which consistently gives products of quality superior to that obtained in the prior art. Other objects and advantages will become apparent from the following description.

The above objects are attained by the instant invention which comprises forming the alkaline earth metal resinate lake of a water-insoluble phthalocyanine coloring matter in the presence of a member of the group consisting of a long chain glyoxalidine, an ammonium salt of a strong acid, and mixtures thereof.

All water-insoluble phthalocyanines are suitable for nited States Patent 2,774,677 Patented Dec. 18, 1956 treatment by the present invention. Metalafree and metal phthalocyanines as well as the various substitution products thereof give excellent results provided they are water-insoluble, e. g. suitable as pigments. The process is also applicable to mixtures of phthalocyanines with other pigments but in such combinations it is essential that the phthalocyanine be the largest component. The physical condition of the pigment to be lak-ed is not critical. Thus products such as obtained in United States Letters Patent No. 2,334,812 and FIAT 1313, vol. III, p. 295, are suitable and give comparable results.

The alkaline earth metal resinate may be derived from rosin and its derivatives such as chlorinated, nitrated, arylated, oxidized, dehydrogenated and hydrogenated abietic acid and rosins, tall oil, Venice turpentine, various other resin acids such as those derived from plants of the genus Angiospermae, e. g., ammoniacum, Gamboge resin, liquid styrax and mastic, and the like. The preferred metal is barium, although other alkaline earth metals may be employed such as calcium and strontium. While the quantity of the alkaline earth metal resinate in the lake may be varied within wide limits, the best balance of properties and dilution is obtained with proportions of from 20 to 30 percent by weight, although proportions of from 5 to percent produce improved results.

The ammonium salts of strong acids which are effective in the process of this invention are ammonium sulfate, ammonium nitrate, ammonium acetate, ammonium phosphate, and ammonium chloride, and the like. We prefer to use ammonium chloride because it is most effective and does not introduce an additional diluent as is the case with ammonium sulfate which causes coprecipitation of the metal sulfate with the like. The lower effective concentrations of ammonium salt is about 0.1 part by Weight per part of pigment. The upper limit is not critical and may be as great as 10 parts. Such high usages do not offer substantial advantages and are therefore not practical economically. Our preferred usage is from 0.5 to 3 parts by weight per part of pigment.

Effective glyoxalidines are water dispersible l-hydroxyethyl glyoxalidines containing long chain hydrocarbon radicals in the 2 position, these being at present commercially available. The length of the hydrocarbon radical may varied from 8 to 18 carbon atoms and may contain unsaturated linkages. Because of ready availability our preferred compound is 1-hydroxyethyl-2-heptadecenyl glyoxalidine. Others, however, are equally effective such as the corresponding 2-octyl and Z-octadecyl glyoxalidines. The amount of glyoxalidine necessary in the attainment of the objects of this invention is 0.01 to 0.20 part by weight per part of pigment. Since substantially all of the glyoxalidine is adsorbed on and remains with the pigment, usages higher than those indicated reduce pigmentary strength without improving properties appreciably.

It is to be noted that both ammonium salts of strong acids and the aforementioned glyoxalidines are separately effective in achieving the, objects of this invention. However, the combination of these agents is particularly effective. In such combination, the amounts of the components fall within the same range of proportions as when used separately.

The conditions under which lake formation occurs may be varied over wide limits and yet give comparable results. Thus, agitation may be varied from mild to extremely vigorous, the sodium, potassium, ammonium or other water soluble salts of the resinmay be used, resins of widely varying grades are effective, the temperature may be varied from 25-100, and the laking operation may be slow or very rapid. The flexibility with which these several variables may be modified is on of v the very substantial advantages of this invention.

In general, a solution of a water-soluble alkaline earth metal salt is mixed with a solution of a water-soluble salt (soap) of a resin acid in the persence of the water-insoluble phthalocyanine coloring matter and the addition agents of this invention. The mixing may occur in any order, it being understood that the ratio of alkaline earth metal salt to resin soap is at least stoichiometric. Thus, the solution of the alkaline earth metal salt may be added to the solution of the resin soap containing the phthalocyanine coloring matter dispersed therein or the resin soap solution may be added to the alkaline earth metal salt solution containing the phthalocyanine coloring matter dispersed therein. The addition agents of this invention may be present in either of the solutions which are mixed to cause precipitation of the metallic resinate on the phthalocyanine coloring matter. It is preferred, however, to carry out the invention by adding the ammonium salt and/or long chain glyoxalidine to a dispersion of the phthalocyanine coloring matter, adding a solution of the resin acid soap to the slurry, and then adding the watersoluble alkaline earth metal salt thereto to cause precipitation of the metallic resinate. Although not absolutely necessary, the slurry containing the phthalocyanine coloring matter and the addition agent is made alkaline before addition of the resin acid soap where too low a pH would cause premature precipitation of the resin acid soap before addition of the alkaline earth metal salt.

Our invention will be further illustrated by the following examples. It is to be understood, however, that it is not restricted thereto. The parts are by weight unless otherwise indicated:

Example 1 45 parts of copper hexadecachlorophthalocyanine as 184 parts of an acid pasted presscake were added to 716 parts of water and the mixture stirred until a homogeneous slurry was obtained. Sufiicient aqueous ammonia to adjust the pH to 7.58, and 4.5 parts of ammonium chloride were added and the mixture heated to 95 C.

A rosin solution made by heating 8 parts of wood rosin, 165 parts of water and 1.6 parts of sodium hydroxide was added to the hot pigment slurry.

The mixture was agitated at 9598 C. for 30 minutes after which a solution of 4.5 parts of barium chloride in 45 parts of water was added. The slurry was then boiled for 30 minutes at which point sufiicient water was added to cool to 65 C.

The product was isolated by filtration, washed and dried.

The resinated copper hexadecachlorophthalocyanine produced was much superior in texture to the product obtained without addition of ammonium chloride.

Example 2 The process of Example 1 was repeated except that instead of 4.5 parts of ammonium chloride, there was used one part of 1-hydroxyethyl-2-heptadecenyl glyoxalidine. The product had properties superior in texture to those of the product obtained in the absence of the l-hydroxyethyl-2-heptadecenyl glyoxalidine or ammonium chloride.

Example 3 160 parts of copper phthalocyanine acid pasted presscake containing 35.2 parts of pigment were slurried in 390 parts of water. One part of l-hydroxyethyl-Z-heptadecenyl glyoxalidine, 7.5 parts of ammonium chloride and sufficient aqueous ammonia to give an alkaline reaction (pH above 8.5) were added. The mixture was stirred at 60-65 C. until homogeneous.

A rosin solution made by heating 14 parts of wood rosin, 155 parts of water and 3.8 parts of sodium hydroxide was added to the pigment slurry.

The mixture was agitated at 60-65 C. for 30 minutes after which a solution of 7.5 parts of barium chloride in parts of water was added. The slurry was heated at the boil for 30 minutes, diluted with water until the temperature was 75 C., and filtered. The filter cake which resulted was washed acid-free and dried.

The resinated copper phthalocyanine produced was of excellent texture and gave desirable rheological properties when formulated into a printing ink.

Substitution of calcium chloride or strontium chloride for the barium chloride employed in the above examples produced substantially similar results.

Other modifications and variations of this invention will be obvious to the person skilled in the art and it is to be understood that such modifications and variations are to be included within the purview of this application and the spirit and scope of the appended claims.

We claim:

1. In a process for the manufacture of a phthalocyanine lake in which a water-insoluble alkaline earth metal resinate is precipitated by reaction between a water soluble alkaline earth metal salt and a water soluble salt of a resin acid in an aqueous medium in the presence of a waterinsoluble phthalocyanine coloring matter, the improvement which comprises effecting the precipitation in the presence of about .01 to 0.2 part by weight per part of pigment of a l-hydroxyethyl glyoxalidine containing a long chain hydrocarbon in the 2 position.

2. A process as defined in claim 1 wherein the precipitation is effected in the presence of l-hydroxyethyl-Z-heptadecenyl glyoxalidine.

3. A process as defined in claim 2 wherein the phthalocyanine coloring matter is copper phthalocyanine.

4. A process as defined in claim 2 wherein the phthalocyanine coloring matter is copper hexadecachlorophthalocyanine.

5. A process as defined in claim 1 wherein the precipitation is efiected in the presence of about 0.1 to 10 parts by weight per part of pigment of an ammonium salt of a strong acid.

6. A process as defined in claim 5 wherein the phthalocyanine coloring matter is copper phthalocyanine.

7. A process as defined in claim 5 wherein the phthalocyanine coloring matter is copper hexadecachlorophthalocyanine.

8. A process as defined in claim 1 wherein said resinate is barium rosinate.

9. A process as defined in claim 2 wherein said resinate is barium rosinate.

10. A process as defined in claim 5 wherein said resinate is barium rosinate.

11. A process as defined in claim 10 wherein said ammonium salt is ammonium chloride.

12. In a process for the manufacture of a phthalocyanine lake in which barium rosinate is precipitated by reaction between barium chloride and sodium rosinate in an aqueous medium in the presence of copper hexadecachlorophthalocyanine, the improvement which comprises effecting the precipitation in the presence of about .01 to 02 part by weight per part of said phthalocyanine of lhydroxyethyl-2-heptadecenyl glyoxalidine.

13. A process as defined in claim 12 wherein the precipitation is effected in the presence of about 0.1 to 10 parts by weight per part of said phthalocyanine of ammonium chloride.

Holzach et al Nov. 23, 1937 Siegel Sept. 19, 1939 

1. IN A PROCESS FOR THE MANUFACTURE OF A PHTHALOCYANINE LAKE IN WHICH A WATER-INSOLUBLE ALKALINE EARTH METAL RESINATE IS PRECIPITATED BY REACTION BETWEEN A WATER SOLUBLE ALKALINE EARTH METAL SALT AND A WATER SOLUBLE SALT OF A RESIN ACID IN AN AQUEOUS MEDIUM IN THE PRESENCE OF A WATERINSOLUBLE PHTHALOCYANINE COLORING MATTER, THE IMPROVEMENT WHICH COMPRISES EFFECTING THE PRECIPITATION IN THE PRESENCE OF ABOUT .01 TO 0.2 PART BY WEIGHT PER PART OF PIGMENT OF A 1-HYDROXYETHYL GLYOXALIDINE CONTAINING A LONG CHAIN HYDROCARBON IN THE 2 POSITION. 